/*
 * Copyright (C) 2009 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <QTECore/qteglobal.h>

#include <assert.h>
#include <math.h>
#include <stdio.h>
#include <string.h>
#include <iostream>
#include "lpicache.h"
#include "matrixsearch.h"
#include "mystdlib.h"
#include "ngram.h"
#include "userdict.h"

namespace ime_pinyin {

#define PRUMING_SCORE 8000.0

MatrixSearch::MatrixSearch() {
  inited_ = false;
  spl_trie_ = SpellingTrie::get_cpinstance();

  reset_pointers_to_null();

  pys_decoded_len_ = 0;
  mtrx_nd_pool_used_ = 0;
  dmi_pool_used_ = 0;
  xi_an_enabled_ = false;
  dmi_c_phrase_ = false;

  assert(kMaxSearchSteps > 0);
  max_sps_len_ = kMaxSearchSteps - 1;
  max_hzs_len_ = kMaxSearchSteps;
}

MatrixSearch::~MatrixSearch() {
  free_resource();
}

void MatrixSearch::reset_pointers_to_null() {
  dict_trie_ = NULL;
  user_dict_ = NULL;
  spl_parser_ = NULL;

  share_buf_ = NULL;

  // The following four buffers are used for decoding, and they are based on
  // share_buf_, no need to delete them.
  mtrx_nd_pool_ = NULL;
  dmi_pool_ = NULL;
  matrix_ = NULL;
  dep_ = NULL;

  // Based on share_buf_, no need to delete them.
  npre_items_ = NULL;
}

bool MatrixSearch::alloc_resource() {
  free_resource();

  dict_trie_ = new DictTrie();
  user_dict_ = static_cast<AtomDictBase*>(new UserDict());
  spl_parser_ = new SpellingParser();

  size_t mtrx_nd_size = sizeof(MatrixNode) * kMtrxNdPoolSize;
  mtrx_nd_size = align_to_size_t(mtrx_nd_size) / sizeof(size_t);
  size_t dmi_size = sizeof(DictMatchInfo) * kDmiPoolSize;
  dmi_size = align_to_size_t(dmi_size) / sizeof(size_t);
  size_t matrix_size = sizeof(MatrixRow) * kMaxRowNum;
  matrix_size = align_to_size_t(matrix_size) / sizeof(size_t);
  size_t dep_size = sizeof(DictExtPara);
  dep_size = align_to_size_t(dep_size) / sizeof(size_t);

  // share_buf's size is determined by the buffers for search.
  share_buf_ = new size_t[mtrx_nd_size + dmi_size + matrix_size + dep_size];

  if (NULL == dict_trie_ || NULL == user_dict_ || NULL == spl_parser_ ||
	  NULL == share_buf_)
	return false;

  // The buffers for search are based on the share buffer
  mtrx_nd_pool_ = reinterpret_cast<MatrixNode*>(share_buf_);
  dmi_pool_ = reinterpret_cast<DictMatchInfo*>(share_buf_ + mtrx_nd_size);
  matrix_ = reinterpret_cast<MatrixRow*>(share_buf_ + mtrx_nd_size + dmi_size);
  dep_ = reinterpret_cast<DictExtPara*>
	  (share_buf_ + mtrx_nd_size + dmi_size + matrix_size);

  // The prediction buffer is also based on the share buffer.
  npre_items_ = reinterpret_cast<NPredictItem*>(share_buf_);
  npre_items_len_ = (mtrx_nd_size + dmi_size + matrix_size + dep_size) *
	  sizeof(size_t) / sizeof(NPredictItem);
  return true;
}

void MatrixSearch::free_resource() {
  if (NULL != dict_trie_)
	delete dict_trie_;

  if (NULL != user_dict_)
	delete user_dict_;

  if (NULL != spl_parser_)
	delete spl_parser_;

  if (NULL != share_buf_)
	delete [] share_buf_;

  reset_pointers_to_null();
}

bool MatrixSearch::init(const char *fn_sys_dict, const char *fn_usr_dict) {
  if (NULL == fn_sys_dict || NULL == fn_usr_dict)
	return false;

  if (!alloc_resource())
	return false;

  if (!dict_trie_->load_dict(fn_sys_dict, 1, kSysDictIdEnd))
	return false;

  // If engine fails to load the user dictionary, reset the user dictionary
  // to NULL.
  if (!user_dict_->load_dict(fn_usr_dict, kUserDictIdStart, kUserDictIdEnd)) {
	delete user_dict_;
	user_dict_ = NULL;
  } else{
	user_dict_->set_total_lemma_count_of_others(NGram::kSysDictTotalFreq);
  }

  reset_search0();

  inited_ = true;
  return true;
}

bool MatrixSearch::init_fd(int sys_fd, long start_offset, long length,
						   const char *fn_usr_dict) {
  if (NULL == fn_usr_dict)
	return false;

  if (!alloc_resource())
	return false;

  if (!dict_trie_->load_dict_fd(sys_fd, start_offset, length, 1, kSysDictIdEnd))
	return false;

  if (!user_dict_->load_dict(fn_usr_dict, kUserDictIdStart, kUserDictIdEnd)) {
	delete user_dict_;
	user_dict_ = NULL;
  } else {
	user_dict_->set_total_lemma_count_of_others(NGram::kSysDictTotalFreq);
  }

  reset_search0();

  inited_ = true;
  return true;
}

void MatrixSearch::init_user_dictionary(const char *fn_usr_dict) {
  assert(inited_);

  if (NULL != user_dict_) {
	delete user_dict_;
	user_dict_ = NULL;
  }

  if (NULL != fn_usr_dict) {
	user_dict_ = static_cast<AtomDictBase*>(new UserDict());
	if (!user_dict_->load_dict(fn_usr_dict, kUserDictIdStart, kUserDictIdEnd)) {
	  delete user_dict_;
	  user_dict_ = NULL;
	}
  }

  reset_search0();
}

bool MatrixSearch::is_user_dictionary_enabled() const {
  return NULL != user_dict_;
}

void MatrixSearch::set_max_lens(size_t max_sps_len, size_t max_hzs_len) {
  if (0 != max_sps_len)
	max_sps_len_ = max_sps_len;
  if (0 != max_hzs_len)
	max_hzs_len_ = max_hzs_len;
}

void MatrixSearch::close() {
  flush_cache();
  free_resource();
  inited_ = false;
}

void MatrixSearch::flush_cache() {
  if (NULL != user_dict_)
	user_dict_->flush_cache();
}

void MatrixSearch::set_xi_an_switch(bool xi_an_enabled) {
  xi_an_enabled_ = xi_an_enabled;
}

bool MatrixSearch::get_xi_an_switch() {
  return xi_an_enabled_;
}

bool MatrixSearch::reset_search() {
  if (!inited_)
	return false;
  return reset_search0();
}

bool MatrixSearch::reset_search0() {
	if (!inited_)
		return false;

	pys_decoded_len_ = 0;
	mtrx_nd_pool_used_ = 0;
	dmi_pool_used_ = 0;

	// Get a MatrixNode from the pool
	matrix_[0].mtrx_nd_pos = mtrx_nd_pool_used_;
	matrix_[0].mtrx_nd_num = 1;
	mtrx_nd_pool_used_ += 1;

	// Update the node, and make it to be a starting node
	MatrixNode *node = mtrx_nd_pool_ + matrix_[0].mtrx_nd_pos;
	node->id = 0;
	node->score = 0;
	node->from = NULL;
	node->step = 0;
	node->dmi_fr = (PoolPosType)-1;

	matrix_[0].dmi_pos = 0;
	matrix_[0].dmi_num = 0;
	matrix_[0].dmi_has_full_id = 1;
	matrix_[0].mtrx_nd_fixed = node;

	lma_start_[0] = 0;
	fixed_lmas_ = 0;
	spl_start_[0] = 0;
	fixed_hzs_ = 0;

	dict_trie_->reset_milestones(0, 0);
	if (NULL != user_dict_)
	  user_dict_->reset_milestones(0, 0);

	return true;
}

bool MatrixSearch::reset_search(size_t ch_pos, bool clear_fixed_this_step,
								bool clear_dmi_this_step,
								bool clear_mtrx_this_step) {
  if (!inited_ || ch_pos > pys_decoded_len_ || ch_pos >= kMaxRowNum)
	return false;

  if (0 == ch_pos) {
	reset_search0();
  } else {
	// Prepare mile stones of this step to clear.
	MileStoneHandle *dict_handles_to_clear = NULL;
	if (clear_dmi_this_step && matrix_[ch_pos].dmi_num > 0) {
	  dict_handles_to_clear = dmi_pool_[matrix_[ch_pos].dmi_pos].dict_handles;
	}

	// If there are more steps, and this step is not allowed to clear, find
	// milestones of next step.
	if (pys_decoded_len_ > ch_pos && !clear_dmi_this_step) {
	  dict_handles_to_clear = NULL;
	  if (matrix_[ch_pos + 1].dmi_num > 0) {
		dict_handles_to_clear =
			dmi_pool_[matrix_[ch_pos + 1].dmi_pos].dict_handles;
	  }
	}

	if (NULL != dict_handles_to_clear) {
	  dict_trie_->reset_milestones(ch_pos, dict_handles_to_clear[0]);
	  if (NULL != user_dict_)
		user_dict_->reset_milestones(ch_pos, dict_handles_to_clear[1]);
	}

	pys_decoded_len_ = ch_pos;

	if (clear_dmi_this_step) {
	  dmi_pool_used_ = matrix_[ch_pos - 1].dmi_pos
					   + matrix_[ch_pos - 1].dmi_num;
	  matrix_[ch_pos].dmi_num = 0;
	} else {
	  dmi_pool_used_ = matrix_[ch_pos].dmi_pos + matrix_[ch_pos].dmi_num;
	}

	if (clear_mtrx_this_step) {
	  mtrx_nd_pool_used_ = matrix_[ch_pos - 1].mtrx_nd_pos
						   + matrix_[ch_pos - 1].mtrx_nd_num;
	  matrix_[ch_pos].mtrx_nd_num = 0;
	} else {
	  mtrx_nd_pool_used_ = matrix_[ch_pos].mtrx_nd_pos
						   + matrix_[ch_pos].mtrx_nd_num;
	}

	// Modify fixed_hzs_
	if (fixed_hzs_ > 0 &&
		((kLemmaIdComposing != lma_id_[0]) ||
		 (kLemmaIdComposing == lma_id_[0] &&
		  spl_start_[c_phrase_.length] <= ch_pos))) {
	  size_t fixed_ch_pos = ch_pos;
	  if (clear_fixed_this_step)
		fixed_ch_pos = fixed_ch_pos > 0 ? fixed_ch_pos - 1 : 0;
	  while (NULL == matrix_[fixed_ch_pos].mtrx_nd_fixed && fixed_ch_pos > 0)
		fixed_ch_pos--;

	  fixed_lmas_ = 0;
	  fixed_hzs_ = 0;
	  if (fixed_ch_pos > 0) {
		while (spl_start_[fixed_hzs_] < fixed_ch_pos)
		  fixed_hzs_++;
		assert(spl_start_[fixed_hzs_] == fixed_ch_pos);

		while (lma_start_[fixed_lmas_] < fixed_hzs_)
		  fixed_lmas_++;
		assert(lma_start_[fixed_lmas_] == fixed_hzs_);
	  }

	  // Re-search the Pinyin string for the unlocked lemma
	  // which was previously fixed.
	  //
	  // Prepare mile stones of this step to clear.
	  MileStoneHandle *dict_handles_to_clear = NULL;
	  if (clear_dmi_this_step && ch_pos == fixed_ch_pos &&
		  matrix_[fixed_ch_pos].dmi_num > 0) {
		dict_handles_to_clear = dmi_pool_[matrix_[fixed_ch_pos].dmi_pos].dict_handles;
	  }

	  // If there are more steps, and this step is not allowed to clear, find
	  // milestones of next step.
	  if (pys_decoded_len_ > fixed_ch_pos && !clear_dmi_this_step) {
		dict_handles_to_clear = NULL;
		if (matrix_[fixed_ch_pos + 1].dmi_num > 0) {
		  dict_handles_to_clear =
			  dmi_pool_[matrix_[fixed_ch_pos + 1].dmi_pos].dict_handles;
		}
	  }

	  if (NULL != dict_handles_to_clear) {
		dict_trie_->reset_milestones(fixed_ch_pos, dict_handles_to_clear[0]);
		if (NULL != user_dict_)
		  user_dict_->reset_milestones(fixed_ch_pos, dict_handles_to_clear[1]);
	  }


	  pys_decoded_len_ = fixed_ch_pos;

	  if (clear_dmi_this_step && ch_pos == fixed_ch_pos) {
		dmi_pool_used_ = matrix_[fixed_ch_pos - 1].dmi_pos
						 + matrix_[fixed_ch_pos - 1].dmi_num;
		matrix_[fixed_ch_pos].dmi_num = 0;
	  } else {
		dmi_pool_used_ = matrix_[fixed_ch_pos].dmi_pos +
			matrix_[fixed_ch_pos].dmi_num;
	  }

	  if (clear_mtrx_this_step && ch_pos == fixed_ch_pos) {
		mtrx_nd_pool_used_ = matrix_[fixed_ch_pos - 1].mtrx_nd_pos
							 + matrix_[fixed_ch_pos - 1].mtrx_nd_num;
		matrix_[fixed_ch_pos].mtrx_nd_num = 0;
	  } else {
		mtrx_nd_pool_used_ = matrix_[fixed_ch_pos].mtrx_nd_pos
							 + matrix_[fixed_ch_pos].mtrx_nd_num;
	  }

	  for (uint16 re_pos = fixed_ch_pos; re_pos < ch_pos; re_pos++) {
		add_char(pys_[re_pos]);
	  }
	} else if (fixed_hzs_ > 0 && kLemmaIdComposing == lma_id_[0]) {
	  for (uint16 subpos = 0; subpos < c_phrase_.sublma_num; subpos++) {
		uint16 splpos_begin = c_phrase_.sublma_start[subpos];
		uint16 splpos_end = c_phrase_.sublma_start[subpos + 1];
		for (uint16 splpos = splpos_begin; splpos < splpos_end; splpos++) {
		  // If ch_pos is in this spelling
		  uint16 spl_start = c_phrase_.spl_start[splpos];
		  uint16 spl_end = c_phrase_.spl_start[splpos + 1];
		  if (ch_pos >= spl_start && ch_pos < spl_end) {
			// Clear everything after this position
			c_phrase_.chn_str[splpos] = static_cast<char16>('\0');
			c_phrase_.sublma_start[subpos + 1] = splpos;
			c_phrase_.sublma_num = subpos + 1;
			c_phrase_.length = splpos;

			if (splpos == splpos_begin) {
			  c_phrase_.sublma_num = subpos;
			}
		  }
		}
	  }

	  // Extend the composing phrase.
	  reset_search0();
	  dmi_c_phrase_ = true;
	  uint16 c_py_pos = 0;
	  while (c_py_pos < spl_start_[c_phrase_.length]) {
		bool b_ac_tmp = add_char(pys_[c_py_pos]);
		assert(b_ac_tmp);
		c_py_pos++;
	  }
	  dmi_c_phrase_ = false;

	  lma_id_num_ = 1;
	  fixed_lmas_ = 1;
	  fixed_lmas_no1_[0] = 0;  // A composing string is always modified.
	  fixed_hzs_ = c_phrase_.length;
	  lma_start_[1] = fixed_hzs_;
	  lma_id_[0] = kLemmaIdComposing;
	  matrix_[spl_start_[fixed_hzs_]].mtrx_nd_fixed = mtrx_nd_pool_ +
		  matrix_[spl_start_[fixed_hzs_]].mtrx_nd_pos;
	}
  }

  return true;
}

void MatrixSearch::del_in_pys(size_t start, size_t len) {
  while (start < kMaxRowNum - len && '\0' != pys_[start]) {
	pys_[start] = pys_[start + len];
	start++;
  }
}

size_t MatrixSearch::search(const char *py, size_t py_len) {
  if (!inited_ || NULL == py)
	return 0;

  // If the search Pinyin string is too long, it will be truncated.
  if (py_len > kMaxRowNum - 1)
	py_len = kMaxRowNum - 1;

  // Compare the new string with the previous one. Find their prefix to
  // increase search efficiency.
  size_t ch_pos = 0;
  for (ch_pos = 0; ch_pos < pys_decoded_len_; ch_pos++) {
	if ('\0' == py[ch_pos] || py[ch_pos] != pys_[ch_pos])
	  break;
  }

  bool clear_fix = true;
  if (ch_pos == pys_decoded_len_)
	clear_fix = false;

  reset_search(ch_pos, clear_fix, false, false);

  memcpy(pys_ + ch_pos, py + ch_pos, py_len - ch_pos);
  pys_[py_len] = '\0';

  while ('\0' != pys_[ch_pos]) {
	if (!add_char(py[ch_pos])) {
	  pys_decoded_len_ = ch_pos;
	  break;
	}
	ch_pos++;
  }

  // Get spelling ids and starting positions.
  get_spl_start_id();

  // If there are too many spellings, remove the last letter until the spelling
  // number is acceptable.
  while (spl_id_num_ > 9) {
	py_len--;
	reset_search(py_len, false, false, false);
	pys_[py_len] = '\0';
	get_spl_start_id();
  }

  prepare_candidates();

  if (kPrintDebug0) {
	printf("--Matrix Node Pool Used: %u\n", mtrx_nd_pool_used_);
	printf("--DMI Pool Used: %u\n", dmi_pool_used_);

	if (kPrintDebug1) {
	  for (PoolPosType pos = 0; pos < dmi_pool_used_; pos++) {
		debug_print_dmi(pos, 1);
	  }
	}
  }

  return ch_pos;
}

size_t MatrixSearch::delsearch(size_t pos, bool is_pos_in_splid,
							   bool clear_fixed_this_step) {
  if (!inited_)
	return 0;

  size_t reset_pos = pos;

  // Out of range for both Pinyin mode and Spelling id mode.
  if (pys_decoded_len_ <= pos) {
	del_in_pys(pos, 1);

	reset_pos = pys_decoded_len_;
	// Decode the string after the un-decoded position
	while ('\0' != pys_[reset_pos]) {
	  if (!add_char(pys_[reset_pos])) {
		pys_decoded_len_ = reset_pos;
		break;
	  }
	  reset_pos++;
	}
	get_spl_start_id();
	prepare_candidates();
	return pys_decoded_len_;
  }

  // Spelling id mode, but out of range.
  if (is_pos_in_splid && spl_id_num_ <= pos)
	return pys_decoded_len_;

  // Begin to handle two modes respectively.
  // Pinyin mode by default
  size_t c_py_len = 0;  // The length of composing phrase's Pinyin
  size_t del_py_len = 1;
  if (!is_pos_in_splid) {
	// Pinyin mode is only allowed to delete beyond the fixed lemmas.
	if (fixed_lmas_ > 0 && pos < spl_start_[lma_start_[fixed_lmas_]])
	  return pys_decoded_len_;

	del_in_pys(pos, 1);

	// If the deleted character is just the one after the last fixed lemma
	if (pos == spl_start_[lma_start_[fixed_lmas_]]) {
	  // If all fixed lemmas have been merged, and the caller of the function
	  // request to unlock the last fixed lemma.
	  if (kLemmaIdComposing == lma_id_[0] && clear_fixed_this_step) {
		// Unlock the last sub lemma in the composing phrase. Because it is not
		// easy to unlock it directly. Instead, we re-decode the modified
		// composing phrase.
		c_phrase_.sublma_num--;
		c_phrase_.length = c_phrase_.sublma_start[c_phrase_.sublma_num];
		reset_pos = spl_start_[c_phrase_.length];
		c_py_len = reset_pos;
	  }
	}
  } else {
	del_py_len = spl_start_[pos + 1] - spl_start_[pos];

	del_in_pys(spl_start_[pos], del_py_len);

	if (pos >= lma_start_[fixed_lmas_]) {
	  c_py_len = 0;
	  reset_pos = spl_start_[pos + 1] - del_py_len;
	} else {
	  c_py_len = spl_start_[lma_start_[fixed_lmas_]] - del_py_len;
	  reset_pos = c_py_len;
	  if (c_py_len > 0)
		merge_fixed_lmas(pos);
	}
  }

  if (c_py_len > 0) {
	assert(c_phrase_.length > 0 && c_py_len ==
		c_phrase_.spl_start[c_phrase_.sublma_start[c_phrase_.sublma_num]]);
	// The composing phrase is valid, reset all search space,
	// and begin a new search which will only extend the composing
	// phrase.
	reset_search0();

	dmi_c_phrase_ = true;
	// Extend the composing phrase.
	uint16 c_py_pos = 0;
	while (c_py_pos < c_py_len) {
	  bool b_ac_tmp = add_char(pys_[c_py_pos]);
	  assert(b_ac_tmp);
	  c_py_pos++;
	}
	dmi_c_phrase_ = false;

	// Fixd the composing phrase as the first choice.
	lma_id_num_ = 1;
	fixed_lmas_ = 1;
	fixed_lmas_no1_[0] = 0;  // A composing string is always modified.
	fixed_hzs_ = c_phrase_.length;
	lma_start_[1] = fixed_hzs_;
	lma_id_[0] = kLemmaIdComposing;
	matrix_[spl_start_[fixed_hzs_]].mtrx_nd_fixed = mtrx_nd_pool_ +
		matrix_[spl_start_[fixed_hzs_]].mtrx_nd_pos;
  } else {
	// Reseting search only clear pys_decoded_len_, but the string is kept.
	reset_search(reset_pos, clear_fixed_this_step, false, false);
  }

  // Decode the string after the delete position.
  while ('\0' != pys_[reset_pos]) {
	if (!add_char(pys_[reset_pos])) {
	  pys_decoded_len_ = reset_pos;
	  break;
	}
	reset_pos++;
  }

  get_spl_start_id();
  prepare_candidates();
  return pys_decoded_len_;
}

size_t MatrixSearch::get_candidate_num() {
  if (!inited_ || 0 == pys_decoded_len_ ||
	  0 == matrix_[pys_decoded_len_].mtrx_nd_num)
	return 0;

  return 1 + lpi_total_;
}

char16* MatrixSearch::get_candidate(size_t cand_id, char16 *cand_str,
									size_t max_len) {
  if (!inited_ || 0 == pys_decoded_len_ || NULL == cand_str)
	return NULL;

  if (0 == cand_id) {
	return get_candidate0(cand_str, max_len, NULL, false);
  } else {
	cand_id--;
  }

  // For this case: the current sentence is a word only, and the user fixed it,
  // so the result will be fixed to the sentence space, and
  // lpi_total_ will be set to 0.
  if (0 == lpi_total_) {
	return get_candidate0(cand_str, max_len, NULL, false);
  }

  LemmaIdType id = lpi_items_[cand_id].id;
  char16 s[kMaxLemmaSize + 1];

  uint16 s_len = lpi_items_[cand_id].lma_len;
  if (s_len > 1) {
	s_len = get_lemma_str(id, s, kMaxLemmaSize + 1);
  } else {
	// For a single character, Hanzi is ready.
	s[0] = lpi_items_[cand_id].hanzi;
	s[1] = static_cast<char16>(0);
  }

  if (s_len > 0 &&  max_len > s_len) {
	utf16_strncpy(cand_str, s, s_len);
	cand_str[s_len] = (char16)'\0';
	return cand_str;
  }

  return NULL;
}

void MatrixSearch::update_dict_freq() {
  if (NULL != user_dict_) {
	// Update the total frequency of all lemmas, including system lemmas and
	// user dictionary lemmas.
	size_t total_freq = user_dict_->get_total_lemma_count();
	dict_trie_->set_total_lemma_count_of_others(total_freq);
  }
}

bool MatrixSearch::add_lma_to_userdict(uint16 lma_fr, uint16 lma_to,
									   float score) {
  (void)(score);
  if (lma_to - lma_fr <= 1 || NULL == user_dict_)
	return false;

  char16 word_str[kMaxLemmaSize + 1];
  uint16 spl_ids[kMaxLemmaSize];

  uint16 spl_id_fr = 0;

  for (uint16 pos = lma_fr; pos < lma_to; pos++) {
	LemmaIdType lma_id = lma_id_[pos];
	if (is_user_lemma(lma_id)) {
	  user_dict_->update_lemma(lma_id, 1, true);
	}
	uint16 lma_len = lma_start_[pos + 1] - lma_start_[pos];
	utf16_strncpy(spl_ids + spl_id_fr, spl_id_ + lma_start_[pos], lma_len);

	uint16 tmp = get_lemma_str(lma_id, word_str + spl_id_fr,
							   kMaxLemmaSize + 1 - spl_id_fr);
	assert(tmp == lma_len);

	tmp = get_lemma_splids(lma_id, spl_ids + spl_id_fr, lma_len, true);
	if (tmp != lma_len) {
	  return false;
	}

	spl_id_fr += lma_len;
  }

  assert(spl_id_fr <= kMaxLemmaSize);

  return user_dict_->put_lemma(static_cast<char16*>(word_str), spl_ids,
								 spl_id_fr, 1);
}

void MatrixSearch::debug_print_dmi(PoolPosType dmi_pos, uint16 nest_level) {
  if (dmi_pos >= dmi_pool_used_) return;

  DictMatchInfo *dmi = dmi_pool_ + dmi_pos;

  if (1 == nest_level) {
	printf("-----------------%u\'th DMI node begin----------->\n", dmi_pos);
  }
  if (dmi->dict_level > 1) {
	debug_print_dmi(dmi->dmi_fr, nest_level + 1);
  }
  printf("---%u\n", dmi->dict_level);
  printf(" MileStone: %x, %x\n", dmi->dict_handles[0], dmi->dict_handles[1]);
  printf(" Spelling : %s, %u\n", SpellingTrie::get_instance().
		 get_spelling_str(dmi->spl_id), dmi->spl_id);
  printf(" Total Pinyin Len: %u\n", dmi->splstr_len);
  if (1 == nest_level) {
	printf("<----------------%u\'th DMI node end--------------\n\n", dmi_pos);
  }
}

bool MatrixSearch::try_add_cand0_to_userdict() {
  size_t new_cand_num = get_candidate_num();
  if (fixed_hzs_ > 0 && 1 == new_cand_num) {
	float score_from = 0;
	uint16 lma_id_from = 0;
	uint16 pos = 0;
	bool modified = false;
	while (pos < fixed_lmas_) {
	  if (lma_start_[pos + 1] - lma_start_[lma_id_from] >
		  static_cast<uint16>(kMaxLemmaSize)) {
		float score_to_add =
			mtrx_nd_pool_[matrix_[spl_start_[lma_start_[pos]]]
			.mtrx_nd_pos].score - score_from;
		if (modified) {
		  score_to_add += 1.0;
		  if (score_to_add > NGram::kMaxScore) {
			score_to_add = NGram::kMaxScore;
		  }
		  add_lma_to_userdict(lma_id_from, pos, score_to_add);
		}
		lma_id_from = pos;
		score_from += score_to_add;

		// Clear the flag for next user lemma.
		modified = false;
	  }

	  if (0 == fixed_lmas_no1_[pos]) {
		modified = true;
	  }
	  pos++;
	}

	// Single-char word is not allowed to add to userdict.
	if (lma_start_[pos] - lma_start_[lma_id_from] > 1) {
	  float score_to_add =
		  mtrx_nd_pool_[matrix_[spl_start_[lma_start_[pos]]]
		  .mtrx_nd_pos].score - score_from;
	  if (modified) {
		score_to_add += 1.0;
		if (score_to_add > NGram::kMaxScore) {
		  score_to_add = NGram::kMaxScore;
		}
		add_lma_to_userdict(lma_id_from, pos, score_to_add);
	  }
	}
  }
  return true;
}

// Choose a candidate, and give new candidates for next step.
// If user finishes selection, we will try to communicate with user dictionary
// to add new items or update score of some existing items.
//
// Basic rule:
// 1. If user selects the first choice:
//    1.1. If the first choice is not a sentence, instead, it is a lemma:
//         1.1.1. If the first choice is a user lemma, notify the user
//                dictionary that a user lemma is hit, and add occuring count
//                by 1.
//         1.1.2. If the first choice is a system lemma, do nothing.
//    1.2. If the first choice is a sentence containing more than one lemma:
//         1.2.1. The whole sentence will be added as a user lemma. If the
//                sentence contains user lemmas, -> hit, and add occuring count
//                by 1.
size_t MatrixSearch::choose(size_t cand_id) {
  if (!inited_ || 0 == pys_decoded_len_)
	return 0;

  if (0 == cand_id) {
	fixed_hzs_ = spl_id_num_;
	matrix_[spl_start_[fixed_hzs_]].mtrx_nd_fixed = mtrx_nd_pool_ +
		matrix_[spl_start_[fixed_hzs_]].mtrx_nd_pos;
	for (size_t pos = fixed_lmas_; pos < lma_id_num_; pos++) {
	  fixed_lmas_no1_[pos] = 1;
	}
	fixed_lmas_ = lma_id_num_;
	lpi_total_ = 0;  // Clean all other candidates.

	// 1. It is the first choice
	if (1 == lma_id_num_) {
	  // 1.1. The first choice is not a sentence but a lemma
	  if (is_user_lemma(lma_id_[0])) {
		// 1.1.1. The first choice is a user lemma, notify the user dictionary
		// that it is hit.
		if (NULL != user_dict_)
		  user_dict_->update_lemma(lma_id_[0], 1, true);
	  } else {
		// 1.1.2. do thing for a system lemma.
	  }
	} else {
	  // 1.2. The first choice is a sentence.
	  // 1.2.1 Try to add the whole sentence to user dictionary, the whole
	  // sentence may be splitted into many items.
	  if (NULL != user_dict_) {
		try_add_cand0_to_userdict();
	  }
	}
	update_dict_freq();
	return 1;
  } else {
	cand_id--;
  }

  // 2. It is not the full sentence candidate.
  // Find the length of the candidate.
  LemmaIdType id_chosen = lpi_items_[cand_id].id;
  LmaScoreType score_chosen = lpi_items_[cand_id].psb;
  size_t cand_len = lpi_items_[cand_id].lma_len;

  assert(cand_len > 0);

  // Notify the atom dictionary that this item is hit.
  if (is_user_lemma(id_chosen)) {
	if (NULL != user_dict_) {
	  user_dict_->update_lemma(id_chosen, 1, true);
	}
	update_dict_freq();
  }

  // 3. Fixed the chosen item.
  // 3.1 Get the steps number.
  size_t step_fr = spl_start_[fixed_hzs_];
  size_t step_to = spl_start_[fixed_hzs_ + cand_len];

  // 3.2 Save the length of the original string.
  size_t pys_decoded_len = pys_decoded_len_;

  // 3.2 Reset the space of the fixed part.
  reset_search(step_to, false, false, true);

  // 3.3 For the last character of the fixed part, the previous DMI
  // information will be kept, while the MTRX information will be re-extended,
  // and only one node will be extended.
  matrix_[step_to].mtrx_nd_num = 0;

  LmaPsbItem lpi_item;
  lpi_item.psb = score_chosen;
  lpi_item.id = id_chosen;

  PoolPosType step_to_dmi_fr = match_dmi(step_to,
										 spl_id_ + fixed_hzs_, cand_len);
  //assert(step_to_dmi_fr != static_cast<PoolPosType>(-1));

  extend_mtrx_nd(matrix_[step_fr].mtrx_nd_fixed, &lpi_item, 1,
				 step_to_dmi_fr, step_to);

  matrix_[step_to].mtrx_nd_fixed = mtrx_nd_pool_ + matrix_[step_to].mtrx_nd_pos;
  mtrx_nd_pool_used_ = matrix_[step_to].mtrx_nd_pos +
					   matrix_[step_to].mtrx_nd_num;

  if (id_chosen == lma_id_[fixed_lmas_])
	fixed_lmas_no1_[fixed_lmas_] = 1;
  else
	fixed_lmas_no1_[fixed_lmas_] = 0;
  lma_id_[fixed_lmas_] = id_chosen;
  lma_start_[fixed_lmas_ + 1] = lma_start_[fixed_lmas_] + cand_len;
  fixed_lmas_++;
  fixed_hzs_ = fixed_hzs_ + cand_len;

  while (step_to != pys_decoded_len) {
	bool b = add_char(pys_[step_to]);
	assert(b);
	step_to++;
  }

  if (fixed_hzs_ < spl_id_num_) {
	prepare_candidates();
  } else {
	lpi_total_ = 0;
	if (NULL != user_dict_) {
	  try_add_cand0_to_userdict();
	}
  }

  return get_candidate_num();
}

size_t MatrixSearch::cancel_last_choice() {
  if (!inited_ || 0 == pys_decoded_len_)
	return 0;

  size_t step_start = 0;
  if (fixed_hzs_ > 0) {
	size_t step_end = spl_start_[fixed_hzs_];
	MatrixNode *end_node = matrix_[step_end].mtrx_nd_fixed;
	assert(NULL != end_node);

	step_start = end_node->from->step;

	if (step_start > 0) {
	  DictMatchInfo *dmi = dmi_pool_ + end_node->dmi_fr;
	  fixed_hzs_ -= dmi->dict_level;
	} else {
	  fixed_hzs_ = 0;
	}

	reset_search(step_start, false, false, false);

	while (pys_[step_start] != '\0') {
	  bool b = add_char(pys_[step_start]);
	  assert(b);
	  step_start++;
	}

	prepare_candidates();
  }
  return get_candidate_num();
}

size_t MatrixSearch::get_fixedlen() {
  if (!inited_ || 0 == pys_decoded_len_)
	return 0;
  return fixed_hzs_;
}

bool MatrixSearch::prepare_add_char(char ch) {
  if (pys_decoded_len_ >= kMaxRowNum - 1 ||
	  (!spl_parser_->is_valid_to_parse(ch) && ch != '\''))
	return false;

  if (dmi_pool_used_ >= kDmiPoolSize) return false;

  pys_[pys_decoded_len_] = ch;
  pys_decoded_len_++;

  MatrixRow *mtrx_this_row = matrix_ + pys_decoded_len_;
  mtrx_this_row->mtrx_nd_pos = mtrx_nd_pool_used_;
  mtrx_this_row->mtrx_nd_num = 0;
  mtrx_this_row->dmi_pos = dmi_pool_used_;
  mtrx_this_row->dmi_num = 0;
  mtrx_this_row->dmi_has_full_id = 0;

  return true;
}

bool MatrixSearch::is_split_at(uint16 pos) {
  return !spl_parser_->is_valid_to_parse(pys_[pos - 1]);
}

void MatrixSearch::fill_dmi(DictMatchInfo *dmi, MileStoneHandle *handles,
							PoolPosType dmi_fr, uint16 spl_id,
							uint16 node_num, unsigned char dict_level,
							bool splid_end_split, unsigned char splstr_len,
							unsigned char all_full_id) {
  (void)(node_num);
  dmi->dict_handles[0] = handles[0];
  dmi->dict_handles[1] = handles[1];
  dmi->dmi_fr = dmi_fr;
  dmi->spl_id = spl_id;
  dmi->dict_level = dict_level;
  dmi->splid_end_split = splid_end_split ? 1 : 0;
  dmi->splstr_len = splstr_len;
  dmi->all_full_id = all_full_id;
  dmi->c_phrase = 0;
}

bool MatrixSearch::add_char(char ch) {
  if (!prepare_add_char(ch))
	return false;
  return add_char_qwerty();
}

bool MatrixSearch::add_char_qwerty() {
  matrix_[pys_decoded_len_].mtrx_nd_num = 0;

  bool spl_matched = false;
  uint16 longest_ext = 0;
  // Extend the search matrix, from the oldest unfixed row. ext_len means
  // extending length.
  for (uint16 ext_len = kMaxPinyinSize + 1; ext_len > 0; ext_len--) {
	if (ext_len > pys_decoded_len_ - spl_start_[fixed_hzs_])
	  continue;

	// Refer to the declaration of the variable dmi_has_full_id for the
	// explanation of this piece of code. In one word, it is used to prevent
	// from the unwise extending of "shoud ou" but allow the reasonable
	// extending of "heng ao", "lang a", etc.
	if (ext_len > 1 && 0 != longest_ext &&
		0 == matrix_[pys_decoded_len_ - ext_len].dmi_has_full_id) {
	  if (xi_an_enabled_)
		continue;
	  else
		break;
	}

	uint16 oldrow = pys_decoded_len_ - ext_len;

	// 0. If that row is before the last fixed step, ignore.
	if (spl_start_[fixed_hzs_] > oldrow)
	  continue;

	// 1. Check if that old row has valid MatrixNode. If no, means that row is
	// not a boundary, either a word boundary or a spelling boundary.
	// If it is for extending composing phrase, it's OK to ignore the 0.
	if (0 == matrix_[oldrow].mtrx_nd_num && !dmi_c_phrase_)
	  continue;

	// 2. Get spelling id(s) for the last ext_len chars.
	uint16 spl_idx;
	bool is_pre = false;
	spl_idx = spl_parser_->get_splid_by_str(pys_ + oldrow,
											ext_len, &is_pre);
	if (is_pre)
	  spl_matched = true;

	if (0 == spl_idx)
	  continue;

	bool splid_end_split = is_split_at(oldrow + ext_len);

	// 3. Extend the DMI nodes of that old row
	// + 1 is to extend an extra node from the root
	for (PoolPosType dmi_pos = matrix_[oldrow].dmi_pos;
		 dmi_pos < matrix_[oldrow].dmi_pos + matrix_[oldrow].dmi_num + 1;
		 dmi_pos++) {
	  DictMatchInfo *dmi = dmi_pool_ + dmi_pos;
	  if (dmi_pos == matrix_[oldrow].dmi_pos + matrix_[oldrow].dmi_num) {
		dmi = NULL;  // The last one, NULL means extending from the root.
	  } else {
		// If the dmi is covered by the fixed arrange, ignore it.
		if (fixed_hzs_ > 0 &&
			pys_decoded_len_ - ext_len - dmi->splstr_len <
			spl_start_[fixed_hzs_]) {
		  continue;
		}
		// If it is not in mode for composing phrase, and the source DMI node
		// is marked for composing phrase, ignore this node.
		if (dmi->c_phrase != 0 && !dmi_c_phrase_) {
		  continue;
		}
	  }

	  // For example, if "gao" is extended, "g ao" is not allowed.
	  // or "zh" has been passed, "z h" is not allowed.
	  // Both word and word-connection will be prevented.
	  if (longest_ext > ext_len) {
		if (NULL == dmi && 0 == matrix_[oldrow].dmi_has_full_id) {
		  continue;
		}

		// "z h" is not allowed.
		if (NULL != dmi && spl_trie_->is_half_id(dmi->spl_id)) {
		  continue;
		}
	  }

	  dep_->splids_extended = 0;
	  if (NULL != dmi) {
		uint16 prev_ids_num = dmi->dict_level;
		if ((!dmi_c_phrase_ && prev_ids_num >= kMaxLemmaSize) ||
			(dmi_c_phrase_ && prev_ids_num >=  kMaxRowNum)) {
		  continue;
		}

		DictMatchInfo *d = dmi;
		while (d) {
		  dep_->splids[--prev_ids_num] = d->spl_id;
		  if ((PoolPosType)-1 == d->dmi_fr)
			break;
		  d = dmi_pool_ + d->dmi_fr;
		}
		assert(0 == prev_ids_num);
		dep_->splids_extended = dmi->dict_level;
	  }
	  dep_->splids[dep_->splids_extended] = spl_idx;
	  dep_->ext_len = ext_len;
	  dep_->splid_end_split = splid_end_split;

	  dep_->id_num = 1;
	  dep_->id_start = spl_idx;
	  if (spl_trie_->is_half_id(spl_idx)) {
		// Get the full id list
		dep_->id_num = spl_trie_->half_to_full(spl_idx, &(dep_->id_start));
		assert(dep_->id_num > 0);
	  }

	  uint16 new_dmi_num;

	  new_dmi_num = extend_dmi(dep_, dmi);

	  if (new_dmi_num > 0) {
		if (dmi_c_phrase_) {
		  dmi_pool_[dmi_pool_used_].c_phrase = 1;
		}
		matrix_[pys_decoded_len_].dmi_num += new_dmi_num;
		dmi_pool_used_ += new_dmi_num;

		if (!spl_trie_->is_half_id(spl_idx))
		  matrix_[pys_decoded_len_].dmi_has_full_id = 1;
	  }

	  // If get candiate lemmas, try to extend the path
	  if (lpi_total_ > 0) {
		uint16 fr_row;
		if (NULL == dmi) {
		  fr_row = oldrow;
		} else {
		  assert(oldrow >= dmi->splstr_len);
		  fr_row = oldrow - dmi->splstr_len;
		}
		for (PoolPosType mtrx_nd_pos = matrix_[fr_row].mtrx_nd_pos;
			 mtrx_nd_pos < matrix_[fr_row].mtrx_nd_pos +
			 matrix_[fr_row].mtrx_nd_num;
			 mtrx_nd_pos++) {
		  MatrixNode *mtrx_nd = mtrx_nd_pool_ + mtrx_nd_pos;

		  extend_mtrx_nd(mtrx_nd, lpi_items_, lpi_total_,
						 dmi_pool_used_ - new_dmi_num, pys_decoded_len_);
		  if (longest_ext == 0)
			longest_ext = ext_len;
		}
	  }
	}  // for dmi_pos
  }  // for ext_len
  mtrx_nd_pool_used_ += matrix_[pys_decoded_len_].mtrx_nd_num;

  if (dmi_c_phrase_)
	return true;

  return (matrix_[pys_decoded_len_].mtrx_nd_num != 0 || spl_matched);
}

void MatrixSearch::prepare_candidates() {
  // Get candiates from the first un-fixed step.
  uint16 lma_size_max = kMaxLemmaSize;
  if (lma_size_max > spl_id_num_ - fixed_hzs_)
	lma_size_max = spl_id_num_ - fixed_hzs_;

  uint16 lma_size = lma_size_max;

  // If the full sentense candidate's unfixed part may be the same with a normal
  // lemma. Remove the lemma candidate in this case.
  char16 fullsent[kMaxLemmaSize + 1];
  char16 *pfullsent = NULL;
  uint16 sent_len;
  pfullsent = get_candidate0(fullsent, kMaxLemmaSize + 1, &sent_len, true);

  // If the unfixed part contains more than one ids, it is not necessary to
  // check whether a lemma's string is the same to the unfixed part of the full
  // sentence candidate, so, set it to NULL;
  if (sent_len > kMaxLemmaSize)
	pfullsent = NULL;

  lpi_total_ = 0;
  size_t lpi_num_full_match = 0;  // Number of items which are fully-matched.
  while (lma_size > 0) {
	size_t lma_num;
	lma_num = get_lpis(spl_id_ + fixed_hzs_, lma_size,
					   lpi_items_ + lpi_total_,
					   size_t(kMaxLmaPsbItems - lpi_total_),
					   pfullsent, lma_size == lma_size_max);

	if (lma_num > 0) {
	  lpi_total_ += lma_num;
	  // For next lemma candidates which are not the longest, it is not
	  // necessary to compare with the full sentence candiate.
	  pfullsent = NULL;
	}
	if (lma_size == lma_size_max) {
	  lpi_num_full_match = lpi_total_;
	}
	lma_size--;
  }

  // Sort those partially-matched items by their unified scores.
  myqsort(lpi_items_ + lpi_num_full_match, lpi_total_ - lpi_num_full_match,
		  sizeof(LmaPsbItem), cmp_lpi_with_unified_psb);

  if (kPrintDebug0) {
	printf("-----Prepare candidates, score:\n");
	for (size_t a = 0; a < lpi_total_; a++) {
	  printf("[%03zu]%u    ", a, lpi_items_[a].psb);
	  if ((a + 1) % 6 == 0) printf("\n");
	}
	printf("\n");
  }

  if (kPrintDebug0) {
	printf("--- lpi_total_ = %zu\n", lpi_total_);
  }
}

const char* MatrixSearch::get_pystr(size_t *decoded_len) {
  if (!inited_ || NULL == decoded_len)
	return NULL;

  *decoded_len = pys_decoded_len_;
  return pys_;
}

void MatrixSearch::merge_fixed_lmas(size_t del_spl_pos) {
  if (fixed_lmas_ == 0)
	return;
  // Update spelling segmentation information first.
  spl_id_num_ -= 1;
  uint16 del_py_len = spl_start_[del_spl_pos + 1] - spl_start_[del_spl_pos];
  for (size_t pos = del_spl_pos; pos <= spl_id_num_; pos++) {
	spl_start_[pos] = spl_start_[pos + 1] - del_py_len;
	if (pos == spl_id_num_)
	  break;
	spl_id_[pos] = spl_id_[pos + 1];
  }

  // Begin to merge.
  uint16 phrase_len = 0;

  // Update the spelling ids to the composing phrase.
  // We need to convert these ids into full id in the future.
  memcpy(c_phrase_.spl_ids, spl_id_, spl_id_num_ * sizeof(uint16));
  memcpy(c_phrase_.spl_start, spl_start_, (spl_id_num_ + 1) * sizeof(uint16));

  // If composing phrase has not been created, first merge all fixed
  //  lemmas into a composing phrase without deletion.
  if (fixed_lmas_ > 1 || kLemmaIdComposing != lma_id_[0]) {
	uint16 bp = 1;  // Begin position of real fixed lemmas.
	// There is no existing composing phrase.
	if (kLemmaIdComposing != lma_id_[0]) {
	  c_phrase_.sublma_num = 0;
	  bp = 0;
	}

	uint16 sub_num = c_phrase_.sublma_num;
	for (uint16 pos = bp; pos <= fixed_lmas_; pos++) {
	  c_phrase_.sublma_start[sub_num + pos - bp] = lma_start_[pos];
	  if (lma_start_[pos] > del_spl_pos) {
		c_phrase_.sublma_start[sub_num + pos - bp] -= 1;
	  }

	  if (pos == fixed_lmas_)
		break;

	  uint16 lma_len;
	  char16 *lma_str = c_phrase_.chn_str +
		  c_phrase_.sublma_start[sub_num] + phrase_len;

	  lma_len = get_lemma_str(lma_id_[pos], lma_str, kMaxRowNum - phrase_len);
	  assert(lma_len == lma_start_[pos + 1] - lma_start_[pos]);
	  phrase_len += lma_len;
	}
	assert(phrase_len == lma_start_[fixed_lmas_]);
	c_phrase_.length = phrase_len;  // will be deleted by 1
	c_phrase_.sublma_num += fixed_lmas_ - bp;
  } else {
	for (uint16 pos = 0; pos <= c_phrase_.sublma_num; pos++) {
	  if (c_phrase_.sublma_start[pos] > del_spl_pos) {
		c_phrase_.sublma_start[pos] -= 1;
	  }
	}
	phrase_len = c_phrase_.length;
  }

  assert(phrase_len > 0);
  if (1 == phrase_len) {
	// After the only one is deleted, nothing will be left.
	fixed_lmas_ = 0;
	return;
  }

  // Delete the Chinese character in the merged phrase.
  // The corresponding elements in spl_ids and spl_start of the
  // phrase have been deleted.
  char16 *chn_str = c_phrase_.chn_str + del_spl_pos;
  for (uint16 pos = 0;
	  pos < c_phrase_.sublma_start[c_phrase_.sublma_num] - del_spl_pos;
	  pos++) {
	chn_str[pos] = chn_str[pos + 1];
  }
  c_phrase_.length -= 1;

  // If the deleted spelling id is in a sub lemma which contains more than
  // one id, del_a_sub will be false; but if the deleted id is in a sub lemma
  // which only contains 1 id, the whole sub lemma needs to be deleted, so
  // del_a_sub will be true.
  bool del_a_sub = false;
  for (uint16 pos = 1; pos <= c_phrase_.sublma_num; pos++) {
	if (c_phrase_.sublma_start[pos - 1] ==
		c_phrase_.sublma_start[pos]) {
	  del_a_sub = true;
	}
	if (del_a_sub) {
	  c_phrase_.sublma_start[pos - 1] =
		  c_phrase_.sublma_start[pos];
	}
  }
  if (del_a_sub)
	c_phrase_.sublma_num -= 1;

  return;
}

void MatrixSearch::get_spl_start_id() {
  lma_id_num_ = 0;
  lma_start_[0] = 0;

  spl_id_num_ = 0;
  spl_start_[0] = 0;
  if (!inited_ || 0 == pys_decoded_len_ ||
	  0 == matrix_[pys_decoded_len_].mtrx_nd_num)
	return;

  // Calculate number of lemmas and spellings
  // Only scan those part which is not fixed.
  lma_id_num_ = fixed_lmas_;
  spl_id_num_ = fixed_hzs_;

  MatrixNode *mtrx_nd = mtrx_nd_pool_ + matrix_[pys_decoded_len_].mtrx_nd_pos;
  while (mtrx_nd != mtrx_nd_pool_) {
	if (fixed_hzs_ > 0) {
	  if (mtrx_nd->step <= spl_start_[fixed_hzs_])
		break;
	}

	// Update the spelling segamentation information
	unsigned char word_splstr_len = 0;
	PoolPosType dmi_fr = mtrx_nd->dmi_fr;
	if ((PoolPosType)-1 != dmi_fr)
	  word_splstr_len = dmi_pool_[dmi_fr].splstr_len;

	while ((PoolPosType)-1 != dmi_fr) {
	  spl_start_[spl_id_num_ + 1] = mtrx_nd->step -
		  (word_splstr_len - dmi_pool_[dmi_fr].splstr_len);
	  spl_id_[spl_id_num_] = dmi_pool_[dmi_fr].spl_id;
	  spl_id_num_++;
	  dmi_fr = dmi_pool_[dmi_fr].dmi_fr;
	}

	// Update the lemma segmentation information
	lma_start_[lma_id_num_ + 1] = spl_id_num_;
	lma_id_[lma_id_num_] = mtrx_nd->id;
	lma_id_num_++;

	mtrx_nd = mtrx_nd->from;
  }

  // Reverse the result of spelling info
  for (size_t pos = fixed_hzs_;
	   pos < fixed_hzs_ + (spl_id_num_ - fixed_hzs_ + 1) / 2; pos++) {
	if (spl_id_num_ + fixed_hzs_ - pos != pos + 1) {
	  spl_start_[pos + 1] ^= spl_start_[spl_id_num_ - pos + fixed_hzs_];
	  spl_start_[spl_id_num_ - pos + fixed_hzs_] ^= spl_start_[pos + 1];
	  spl_start_[pos + 1] ^= spl_start_[spl_id_num_ - pos + fixed_hzs_];

	  spl_id_[pos] ^= spl_id_[spl_id_num_ + fixed_hzs_ - pos - 1];
	  spl_id_[spl_id_num_ + fixed_hzs_- pos - 1] ^= spl_id_[pos];
	  spl_id_[pos] ^= spl_id_[spl_id_num_ + fixed_hzs_- pos - 1];
	}
  }

  // Reverse the result of lemma info
  for (size_t pos = fixed_lmas_;
	   pos < fixed_lmas_ + (lma_id_num_ - fixed_lmas_ + 1) / 2; pos++) {
	assert(lma_id_num_ + fixed_lmas_ - pos - 1 >= pos);

	if (lma_id_num_ + fixed_lmas_ - pos > pos + 1) {
	  lma_start_[pos + 1] ^= lma_start_[lma_id_num_ - pos + fixed_lmas_];
	  lma_start_[lma_id_num_ - pos + fixed_lmas_] ^= lma_start_[pos + 1];
	  lma_start_[pos + 1] ^= lma_start_[lma_id_num_ - pos + fixed_lmas_];

	  lma_id_[pos] ^= lma_id_[lma_id_num_ - 1 - pos + fixed_lmas_];
	  lma_id_[lma_id_num_ - 1 - pos + fixed_lmas_] ^= lma_id_[pos];
	  lma_id_[pos] ^= lma_id_[lma_id_num_ - 1 - pos + fixed_lmas_];
	}
  }

  for (size_t pos = fixed_lmas_ + 1; pos <= lma_id_num_; pos++) {
	if (pos < lma_id_num_)
	  lma_start_[pos] = lma_start_[pos - 1] +
		  (lma_start_[pos] - lma_start_[pos + 1]);
	else
	  lma_start_[pos] = lma_start_[pos - 1] + lma_start_[pos] -
		  lma_start_[fixed_lmas_];
  }

  // Find the last fixed position
  fixed_hzs_ = 0;
  for (size_t pos = spl_id_num_; pos > 0; pos--) {
	if (NULL != matrix_[spl_start_[pos]].mtrx_nd_fixed) {
	  fixed_hzs_ = pos;
	  break;
	}
  }

  return;
}

size_t MatrixSearch::get_spl_start(const uint16 *&spl_start) {
  get_spl_start_id();
  spl_start = spl_start_;
  return spl_id_num_;
}

size_t MatrixSearch::extend_dmi(DictExtPara *dep, DictMatchInfo *dmi_s) {
  if (dmi_pool_used_ >= kDmiPoolSize) return 0;

  if (dmi_c_phrase_)
	return extend_dmi_c(dep, dmi_s);

  LpiCache& lpi_cache = LpiCache::get_instance();
  uint16 splid = dep->splids[dep->splids_extended];

  bool cached = false;
  if (0 == dep->splids_extended)
	cached = lpi_cache.is_cached(splid);

  // 1. If this is a half Id, get its corresponding full starting Id and
  // number of full Id.
  size_t ret_val = 0;
  PoolPosType mtrx_dmi_fr = (PoolPosType)-1;  // From which dmi node
  (void)(mtrx_dmi_fr);

  lpi_total_ = 0;

  MileStoneHandle from_h[3];
  from_h[0] = 0;
  from_h[1] = 0;

  if (0 != dep->splids_extended) {
	from_h[0] = dmi_s->dict_handles[0];
	from_h[1] = dmi_s->dict_handles[1];
  }

  // 2. Begin exgtending in the system dictionary
  size_t lpi_num = 0;
  MileStoneHandle handles[2];
  handles[0] = handles[1] = 0;
  if (from_h[0] > 0 || NULL == dmi_s) {
	handles[0] = dict_trie_->extend_dict(from_h[0], dep, lpi_items_,
										 kMaxLmaPsbItems, &lpi_num);
  }
  if (handles[0] > 0)
	lpi_total_ = lpi_num;

  if (NULL == dmi_s) {  // from root
	assert(0 != handles[0]);
	mtrx_dmi_fr = dmi_pool_used_;
  }

  // 3. Begin extending in the user dictionary
  if (NULL != user_dict_ && (from_h[1] > 0 || NULL == dmi_s)) {
	handles[1] = user_dict_->extend_dict(from_h[1], dep,
										 lpi_items_ + lpi_total_,
										 kMaxLmaPsbItems - lpi_total_,
										 &lpi_num);
	if (handles[1] > 0) {
	  if (kPrintDebug0) {
		for (size_t t = 0; t < lpi_num; t++) {
		  std::cout << "--Extend in user dict: uid:"
					<< lpi_items_[lpi_total_ + t].id
					<< " uscore:"
					<< lpi_items_[lpi_total_ + t].psb
					<< std::endl;
		}
	  }
	  lpi_total_ += lpi_num;
	}
  }

  if (0 != handles[0] || 0 != handles[1]) {
	if (dmi_pool_used_ >= kDmiPoolSize) return 0;

	DictMatchInfo *dmi_add = dmi_pool_ + dmi_pool_used_;
	if (NULL == dmi_s) {
	  fill_dmi(dmi_add, handles,
			   (PoolPosType)-1, splid,
			   1, 1, dep->splid_end_split, dep->ext_len,
			   spl_trie_->is_half_id(splid) ? 0 : 1);
	} else {
	  fill_dmi(dmi_add, handles,
			   dmi_s - dmi_pool_, splid, 1,
			   dmi_s->dict_level + 1, dep->splid_end_split,
			   dmi_s->splstr_len + dep->ext_len,
			   spl_trie_->is_half_id(splid) ? 0 : dmi_s->all_full_id);
	}

	ret_val = 1;
  }

  if (!cached) {
	if (0 == lpi_total_)
	  return ret_val;

	if (kPrintDebug0) {
	  printf("--- lpi_total_ = %zu\n", lpi_total_);
	}

	myqsort(lpi_items_, lpi_total_, sizeof(LmaPsbItem), cmp_lpi_with_psb);
	if (NULL == dmi_s && spl_trie_->is_half_id(splid))
	  lpi_total_ = lpi_cache.put_cache(splid, lpi_items_, lpi_total_);
  } else {
	assert(spl_trie_->is_half_id(splid));
	lpi_total_ = lpi_cache.get_cache(splid, lpi_items_, kMaxLmaPsbItems);
  }

  return ret_val;
}

size_t MatrixSearch::extend_dmi_c(DictExtPara *dep, DictMatchInfo *dmi_s) {
  lpi_total_ = 0;

  uint16 pos = dep->splids_extended;
  assert(dmi_c_phrase_);
  if (pos >= c_phrase_.length)
	return 0;

  uint16 splid = dep->splids[pos];
  if (splid == c_phrase_.spl_ids[pos]) {
	DictMatchInfo *dmi_add = dmi_pool_ + dmi_pool_used_;
	MileStoneHandle handles[2];  // Actually never used.
	if (NULL == dmi_s)
	  fill_dmi(dmi_add, handles,
			   (PoolPosType)-1, splid,
			   1, 1, dep->splid_end_split, dep->ext_len,
			   spl_trie_->is_half_id(splid) ? 0 : 1);
	else
	  fill_dmi(dmi_add, handles,
			   dmi_s - dmi_pool_, splid, 1,
			   dmi_s->dict_level + 1, dep->splid_end_split,
			   dmi_s->splstr_len + dep->ext_len,
			   spl_trie_->is_half_id(splid) ? 0 : dmi_s->all_full_id);

	if (pos == c_phrase_.length - 1) {
	  lpi_items_[0].id = kLemmaIdComposing;
	  lpi_items_[0].psb = 0;  // 0 is bigger than normal lemma score.
	  lpi_total_ = 1;
	}
	return 1;
  }
  return 0;
}

size_t MatrixSearch::extend_mtrx_nd(MatrixNode *mtrx_nd, LmaPsbItem lpi_items[],
									size_t lpi_num, PoolPosType dmi_fr,
									size_t res_row) {
  assert(NULL != mtrx_nd);
  matrix_[res_row].mtrx_nd_fixed = NULL;

  if (mtrx_nd_pool_used_ >= kMtrxNdPoolSize - kMaxNodeARow)
	return 0;

  if (0 == mtrx_nd->step) {
	// Because the list is sorted, if the source step is 0, it is only
	// necessary to pick up the first kMaxNodeARow items.
	if (lpi_num > kMaxNodeARow)
	  lpi_num = kMaxNodeARow;
  }

  MatrixNode *mtrx_nd_res_min = mtrx_nd_pool_ + matrix_[res_row].mtrx_nd_pos;
  for (size_t pos = 0; pos < lpi_num; pos++) {
	float score = mtrx_nd->score + lpi_items[pos].psb;
	if (pos > 0 && score - PRUMING_SCORE > mtrx_nd_res_min->score)
	  break;

	// Try to add a new node
	size_t mtrx_nd_num = matrix_[res_row].mtrx_nd_num;
	MatrixNode *mtrx_nd_res = mtrx_nd_res_min + mtrx_nd_num;
	bool replace = false;
	// Find its position
	while (mtrx_nd_res > mtrx_nd_res_min && score < (mtrx_nd_res - 1)->score) {
	  if (static_cast<size_t>(mtrx_nd_res - mtrx_nd_res_min) < kMaxNodeARow)
		*mtrx_nd_res = *(mtrx_nd_res - 1);
	  mtrx_nd_res--;
	  replace = true;
	}
	if (replace || (mtrx_nd_num < kMaxNodeARow &&
		matrix_[res_row].mtrx_nd_pos + mtrx_nd_num < kMtrxNdPoolSize)) {
	  mtrx_nd_res->id = lpi_items[pos].id;
	  mtrx_nd_res->score = score;
	  mtrx_nd_res->from = mtrx_nd;
	  mtrx_nd_res->dmi_fr = dmi_fr;
	  mtrx_nd_res->step = res_row;
	  if (matrix_[res_row].mtrx_nd_num < kMaxNodeARow)
		matrix_[res_row].mtrx_nd_num++;
	}
  }
  return matrix_[res_row].mtrx_nd_num;
}

PoolPosType MatrixSearch::match_dmi(size_t step_to, uint16 spl_ids[],
									uint16 spl_id_num) {
  if (pys_decoded_len_ < step_to || 0 == matrix_[step_to].dmi_num) {
	return static_cast<PoolPosType>(-1);
  }

  for (PoolPosType dmi_pos = 0; dmi_pos < matrix_[step_to].dmi_num; dmi_pos++) {
	DictMatchInfo *dmi = dmi_pool_ + matrix_[step_to].dmi_pos + dmi_pos;

	if (dmi->dict_level != spl_id_num)
	  continue;

	bool matched = true;
	for (uint16 spl_pos = 0; spl_pos < spl_id_num; spl_pos++) {
	  if (spl_ids[spl_id_num - spl_pos - 1] != dmi->spl_id) {
		matched = false;
		break;
	  }

	  dmi = dmi_pool_ + dmi->dmi_fr;
	}
	if (matched) {
	  return matrix_[step_to].dmi_pos + dmi_pos;
	}
  }

  return static_cast<PoolPosType>(-1);
}

char16* MatrixSearch::get_candidate0(char16 *cand_str, size_t max_len,
									 uint16 *retstr_len,
									 bool only_unfixed) {
  if (pys_decoded_len_ == 0 ||
	  matrix_[pys_decoded_len_].mtrx_nd_num == 0)
	return NULL;

  LemmaIdType idxs[kMaxRowNum];
  size_t id_num = 0;

  MatrixNode *mtrx_nd = mtrx_nd_pool_ + matrix_[pys_decoded_len_].mtrx_nd_pos;

  if (kPrintDebug0) {
	printf("--- sentence score: %f\n", mtrx_nd->score);
  }

  if (kPrintDebug1) {
	printf("==============Sentence DMI (reverse order) begin===========>>\n");
  }

  while (mtrx_nd != NULL) {
	idxs[id_num] = mtrx_nd->id;
	id_num++;

	if (kPrintDebug1) {
	   printf("---MatrixNode [step: %u, lma_idx: %zu, total score:%.5f]\n",
			  mtrx_nd->step, mtrx_nd->id, mtrx_nd->score);
	   debug_print_dmi(mtrx_nd->dmi_fr, 1);
	}

	mtrx_nd = mtrx_nd->from;
  }

  if (kPrintDebug1) {
	printf("<<==============Sentence DMI (reverse order) end=============\n");
  }

  size_t ret_pos = 0;
  do {
	id_num--;
	if (0 == idxs[id_num])
	  continue;

	char16 str[kMaxLemmaSize + 1];
	uint16 str_len = get_lemma_str(idxs[id_num], str, kMaxLemmaSize + 1);
	if (str_len > 0 && ((!only_unfixed && max_len - ret_pos > str_len) ||
		(only_unfixed && max_len - ret_pos + fixed_hzs_ > str_len))) {
	  if (!only_unfixed)
		utf16_strncpy(cand_str + ret_pos, str, str_len);
	  else if (ret_pos >= fixed_hzs_)
		utf16_strncpy(cand_str + ret_pos - fixed_hzs_, str, str_len);

	  ret_pos += str_len;
	} else {
	  return NULL;
	}
  } while (id_num != 0);

  if (!only_unfixed) {
	if (NULL != retstr_len)
	  *retstr_len = ret_pos;
	cand_str[ret_pos] = (char16)'\0';
  } else {
	if (NULL != retstr_len)
	  *retstr_len = ret_pos - fixed_hzs_;
	cand_str[ret_pos - fixed_hzs_] = (char16)'\0';
  }
  return cand_str;
}

size_t MatrixSearch::get_lpis(const uint16* splid_str, size_t splid_str_len,
							  LmaPsbItem* lma_buf, size_t max_lma_buf,
							  const char16 *pfullsent, bool sort_by_psb) {
  if (splid_str_len > kMaxLemmaSize)
	return 0;

  size_t num1 = dict_trie_->get_lpis(splid_str, splid_str_len,
									 lma_buf, max_lma_buf);
  size_t num2 = 0;
  if (NULL != user_dict_) {
	num2 = user_dict_->get_lpis(splid_str, splid_str_len,
						 lma_buf + num1, max_lma_buf - num1);
  }

  size_t num = num1 + num2;

  if (0 == num)
	return 0;

  // Remove repeated items.
  if (splid_str_len > 1) {
	LmaPsbStrItem *lpsis = reinterpret_cast<LmaPsbStrItem*>(lma_buf + num);
	size_t lpsi_num = (max_lma_buf - num) * sizeof(LmaPsbItem) /
		sizeof(LmaPsbStrItem);
	//assert(lpsi_num > num);
	if (num > lpsi_num) num = lpsi_num;
	lpsi_num = num;

	for (size_t pos = 0; pos < lpsi_num; pos++) {
	  lpsis[pos].lpi = lma_buf[pos];
	  get_lemma_str(lma_buf[pos].id, lpsis[pos].str, kMaxLemmaSize + 1);
	}

	myqsort(lpsis, lpsi_num, sizeof(LmaPsbStrItem), cmp_lpsi_with_str);

	size_t remain_num = 0;
	for (size_t pos = 0; pos < lpsi_num; pos++) {
	  if (pos > 0 && utf16_strcmp(lpsis[pos].str, lpsis[pos - 1].str) == 0) {
		if (lpsis[pos].lpi.psb < lpsis[pos - 1].lpi.psb) {
		  assert(remain_num > 0);
		  lma_buf[remain_num - 1] = lpsis[pos].lpi;
		}
		continue;
	  }
	  if (NULL != pfullsent && utf16_strcmp(lpsis[pos].str, pfullsent) == 0)
		continue;

	  lma_buf[remain_num] = lpsis[pos].lpi;
	  remain_num++;
	}

	// Update the result number
	num = remain_num;
  } else {
	// For single character, some characters have more than one spelling, for
	// example, "de" and "di" are all valid for a Chinese character, so when
	// the user input  "d", repeated items are generated.
	// For single character lemmas, Hanzis will be gotten
	for (size_t pos = 0; pos < num; pos++) {
	  char16 hanzis[2];
	  get_lemma_str(lma_buf[pos].id, hanzis, 2);
	  lma_buf[pos].hanzi = hanzis[0];
	}

	myqsort(lma_buf, num, sizeof(LmaPsbItem), cmp_lpi_with_hanzi);

	size_t remain_num = 0;
	for (size_t pos = 0; pos < num; pos++) {
	  if (pos > 0 && lma_buf[pos].hanzi == lma_buf[pos - 1].hanzi) {
		if (NULL != pfullsent &&
			static_cast<char16>(0) == pfullsent[1] &&
			lma_buf[pos].hanzi == pfullsent[0])
		  continue;

		if (lma_buf[pos].psb < lma_buf[pos - 1].psb) {
		  assert(remain_num > 0);
		  assert(lma_buf[remain_num - 1].hanzi == lma_buf[pos].hanzi);
		  lma_buf[remain_num - 1] = lma_buf[pos];
		}
		continue;
	  }
	  if (NULL != pfullsent &&
		  static_cast<char16>(0) == pfullsent[1] &&
		  lma_buf[pos].hanzi == pfullsent[0])
		  continue;

	  lma_buf[remain_num] = lma_buf[pos];
	  remain_num++;
	}

	num = remain_num;
  }

  if (sort_by_psb) {
	myqsort(lma_buf, num, sizeof(LmaPsbItem), cmp_lpi_with_psb);
  }
  return num;
}

uint16 MatrixSearch::get_lemma_str(LemmaIdType id_lemma, char16 *str_buf,
								   uint16 str_max) {
  uint16 str_len = 0;

  if (is_system_lemma(id_lemma)) {
	str_len = dict_trie_->get_lemma_str(id_lemma, str_buf, str_max);
  } else if (is_user_lemma(id_lemma)) {
	if (NULL != user_dict_) {
	  str_len = user_dict_->get_lemma_str(id_lemma, str_buf, str_max);
	} else {
	  str_len = 0;
	  str_buf[0] = static_cast<char16>('\0');
	}
  } else if (is_composing_lemma(id_lemma)) {
	if (str_max <= 1)
	  return 0;
	str_len = c_phrase_.sublma_start[c_phrase_.sublma_num];
	if (str_len > str_max - 1)
	  str_len = str_max - 1;
	utf16_strncpy(str_buf, c_phrase_.chn_str, str_len);
	str_buf[str_len] = (char16)'\0';
	return str_len;
  }

  return str_len;
}

uint16 MatrixSearch::get_lemma_splids(LemmaIdType id_lemma, uint16 *splids,
									  uint16 splids_max, bool arg_valid) {
  uint16 splid_num = 0;

  if (arg_valid) {
	for (splid_num = 0; splid_num < splids_max; splid_num++) {
	  if (spl_trie_->is_half_id(splids[splid_num]))
		break;
	}
	if (splid_num == splids_max)
	  return splid_num;
  }

  if (is_system_lemma(id_lemma)) {
	splid_num = dict_trie_->get_lemma_splids(id_lemma, splids, splids_max,
											  arg_valid);
  } else if (is_user_lemma(id_lemma)) {
	if (NULL != user_dict_) {
	  splid_num = user_dict_->get_lemma_splids(id_lemma, splids, splids_max,
											   arg_valid);
	} else {
	  splid_num = 0;
	}
  } else if (is_composing_lemma(id_lemma)) {
	if (c_phrase_.length > splids_max) {
	  return 0;
	}
	for (uint16 pos = 0; pos < c_phrase_.length; pos++) {
	  splids[pos] = c_phrase_.spl_ids[pos];
	  if (spl_trie_->is_half_id(splids[pos])) {
		return 0;
	  }
	}
  }
  return splid_num;
}

size_t MatrixSearch::inner_predict(const char16 *fixed_buf, uint16 fixed_len,
								   char16 predict_buf[][kMaxPredictSize + 1],
								   size_t buf_len) {
  size_t res_total = 0;
  memset(npre_items_, 0, sizeof(NPredictItem) * npre_items_len_);
  // In order to shorten the comments, j-character candidates predicted by
  // i-character prefix are called P(i,j). All candiates predicted by
  // i-character prefix are called P(i,*)
  // Step 1. Get P(kMaxPredictSize, *) and sort them, here
  // P(kMaxPredictSize, *) == P(kMaxPredictSize, 1)
  for (size_t len = fixed_len; len >0; len--) {
	// How many blank items are available
	size_t this_max = npre_items_len_ - res_total;
	size_t res_this;
	// If the history is longer than 1, and we can not get prediction from
	// lemmas longer than 2, in this case, we will add lemmas with
	// highest scores as the prediction result.
	if (fixed_len > 1 && 1 == len && 0 == res_total) {
	  // Try to find if recent n (n>1) characters can be a valid lemma in system
	  // dictionary.
	  bool nearest_n_word = false;
	  for (size_t nlen = 2; nlen <= fixed_len; nlen++) {
		if (dict_trie_->get_lemma_id(fixed_buf + fixed_len - nlen, nlen) > 0) {
		  nearest_n_word = true;
		  break;
		}
	  }
	  res_this = dict_trie_->predict_top_lmas(nearest_n_word ? len : 0,
											  npre_items_ + res_total,
											  this_max, res_total);
	  res_total += res_this;
	}

	// How many blank items are available
	this_max = npre_items_len_ - res_total;
	res_this = 0;
	if (!kOnlyUserDictPredict) {
	  res_this =
		  dict_trie_->predict(fixed_buf + fixed_len - len, len,
							  npre_items_ + res_total, this_max,
							  res_total);
	}

	if (NULL != user_dict_) {
	  res_this = res_this +
				 user_dict_->predict(fixed_buf + fixed_len - len, len,
									 npre_items_ + res_total + res_this,
									 this_max - res_this, res_total + res_this);
	}

	if (kPredictLimitGt1) {
	  myqsort(npre_items_ + res_total, res_this, sizeof(NPredictItem),
			  cmp_npre_by_score);

	  if (len > 3) {
		if (res_this > kMaxPredictNumByGt3)
		  res_this = kMaxPredictNumByGt3;
	  } else if (3 == len) {
		if (res_this > kMaxPredictNumBy3)
		  res_this = kMaxPredictNumBy3;
	  } else if (2 == len) {
		if (res_this > kMaxPredictNumBy2)
		  res_this = kMaxPredictNumBy2;
	  }
	}

	res_total += res_this;
  }

  res_total = remove_duplicate_npre(npre_items_, res_total);

  if (kPreferLongHistoryPredict) {
	myqsort(npre_items_, res_total, sizeof(NPredictItem),
			cmp_npre_by_hislen_score);
  } else {
	myqsort(npre_items_, res_total, sizeof(NPredictItem),
			cmp_npre_by_score);
  }

  if (buf_len < res_total) {
	res_total = buf_len;
  }

  if (kPrintDebug2) {
	printf("/////////////////Predicted Items Begin////////////////////>>\n");
	for (size_t i = 0; i < res_total; i++) {
	  printf("---");
	  for (size_t j = 0; j < kMaxPredictSize; j++) {
		printf("%d  ", npre_items_[i].pre_hzs[j]);
	  }
	  printf("\n");
	}
	printf("<<///////////////Predicted Items End////////////////////////\n");
  }

  for (size_t i = 0; i < res_total; i++) {
	utf16_strncpy(predict_buf[i], npre_items_[i].pre_hzs,
				  kMaxPredictSize);
	predict_buf[i][kMaxPredictSize] = '\0';
  }

  return res_total;
}

size_t MatrixSearch::get_predicts(const char16 fixed_buf[],
								  char16 predict_buf[][kMaxPredictSize + 1],
								  size_t buf_len) {
  size_t fixed_len = utf16_strlen(fixed_buf);
  if (0 ==fixed_len || fixed_len > kMaxPredictSize || 0 == buf_len)
	return 0;

  return inner_predict(fixed_buf, fixed_len, predict_buf, buf_len);
}

}  // namespace ime_pinyin
